Propeller



F 1933- s. F. HOUSTON PROPELLER Filed Aug. 4, 1930 2 Sheets-Sheet l Feb. 28; 1933. s. F. HOUSTON PROPELLER Filed Aug. 4, 1930 2 Sheets-Sheet 2 more particularly Patented Feb. 28, 1933 UNITED STATES PATENT OFFICE GEORGJ: r. HOUSTON,

CORPORATION, OF EAST ORANGE, NEW JERSEY, A CORPORATION OF INDIANA PROPELLER Application filed. August 4, 1930. Serial no. 472,951.

This invention relates to propellers .and to propellers through the blades of which fluid is adapted to be exhausted,

Heretofore, it has been proposed to provide propellers with means enabling fluid to be passed through the blades and numerous advantages and increased etliciencies in operation have been realized by thense of such propellers, especially in instances of aircraft installations, wherein the fluid may comprise the exhaust gases of an internal combustion engine. In installations of the last-mentioned character, various meanshavebeen employed whereby the rotating hollow blades may be operatively connected with the exhaust passages of the engine to enable the gases therein to be led to the through the blades.

It is one of the objects of the present inventionto provide a novel propeller construction wherein fluid is exhausted through the blades thereof.

It may be highly desirable, in certain instances wherein, for example, a fluid-exhaust! ing propeller is employed on aircraft,-to provi e means for varying the angularity or pitch of the blades while the propeller'is in operation,'there resulting from such combination not only an increased engine efliciency due to the exhausting of the gases through the propeller blades, but also a greatly increased the reduction in skin friction due to the fluid issuing from said blades and an increased propeller thrust and other increased. efi'ective forces due to the variable pitch feature.

Itiis accordingly another object of the present invention to provide a novel propeller including fluid-exhausting. means together with means to vary the pitch of the blades while the same are rotating.

Another object is to provide in an aircraft propeller, novel means enabling the engine exhaust gases to be discharged through the propeller blades.

A further object is to provide in an exhaust gas propeller, novel means for heat insulating the driving shaft and bearings therefor from the heated exhaust gases.

atmosphere propeller efficiency because of A still further object is to provide in a propeller, a novel arrangement-of parts whereby the exhaust gases from an internal combustion engine may be discharged to atmosphere through the blades thereof and wherein the blades may about their longitudinal axes to vary the pitch, the said arrangement being compact, light in weight and easily assembled.

The above and other objects of the invention will appear more fully hereinafter from the following detailed description when taken in connection with the accompanying drawings. -It is to be expressly understood, however, that the drawings are for purposes of illustration only and are not to be taken as a definition of the limits of the invention,

reference being had for this purpose to the appended claims.

In the drawings, characters refer to like parts throughout the several views 1 Figure I is a vertical section illustrating one form of propeller constructed in accordance with the present invention; and

Figure 2 is a view similar to Figure 1 illus- Era'ting a slightly modified form of the inven- Referring more particularly to Figure 1, the present invention is illustrated as being embodied in a propeller having a hub 3, drivably connected to a may-be driven by an engine, a forwardly extending stationary portion of which is shown at 5, the said hub beirig adapted to support a plurality of hollow blades 6 through which the exhaust gases from the engine are conducted by means to be particularly referred to hereinafter.

The shaft 4, rotatably supported with rethreadedly received bythe outer end of the wherein like reference shaft 4, which latter- OF SOUTH BEND, INDIANA, ASSIGNOR TO BENDIX RESEARCH be rotated, during operation,

desired.)

In order to drivably connect the hub 3 with the blades 6, the former is provided with two or more radially extending sockets 11 in which the root ends of said blades are rotatably supported. As shown, each blade root end has clamped thereon, a split sleeve 12, provided internally with a plurality-ofannular shear shoulders 13 adapted to be received in corresponding recesses 14 on the blade root,and externally with an annular shoulder 15 forming a seat for a ball thrust bearing 16 the other seat therefor co-operating with a rim nut 17 threaded into the open endof the societ. Packing means 17 and a cap member 17 co-operating therewith, may be provided in order to prevent seepage of oil from the bearing- 16 outwardly.

Means are provided for varying the pitch orangularityof the hollow blades while the propeller is rotating. To this end the split sleeve 12, carrying each blade is rotatably supported in the socket 11.by means of ball bearings 18 and 19, and between such bearings and secured to the sleeve in; a suitable manner is a ring gear 20 constantly in mesh with a longitudinally movable rack 21 extending through suitable apertures provided in the hub socket. It will be understood that a rack is provided tor each blade and that movement of said racks axially of the driving shaft will rotate the blades about their longitudinal axes to vary their angularity or pitch.

. In order to "impart such movement to the racks during rotation of the propeller, the

inner end of each rack is suitably secured to an externally grooved annular member 22 concentrically arran ed .withlrespect to the shaft 4. 7 As willbe understood,'the member 22. rotates with the propeller assembly. Any suitable non-rotatable means capable of longitudinal movement with respect tothe driving shaft,'may be employed for shifting said member 22 and the toothed racks con-- nected thereto, laterally, to effect rotation of the blades in their respective sockets. As shown, such means may comprise a rod 23 connected through a suitable pivoted bell crank, the end of. which is provided with a member 24 extending into the grooved outer peri hery of the'member 22.

cans are provided for conducting the exhaust gases from the engine to the interior of said hollow blades and thence to atmosphere,

and such means are preferably so arranged as to be operable not only during periods of operation wherein 'the pitch of the blades l emains unchanged, but also during such time in operatiomwhen the pitch-changing mechanism is being operated to effect an alteration in the blade angularity. In the form of the invention illustrated; such means include a stationary collector ring'29 which may be provided with a circumferential outwardlyextending flange 30 over which a flange 31 "formed on a rotating collector ring 32 is adapted to,be spun or otherwise operated upon in order to form a substantially frictionless and gas-tight ]oint. A plurality of rotation of the pr0peller,.will flow in the diexhaust pipes 33, leading to engine exhaust rection of the arrows through a plurality of slots 39 arranged adjacent the root end of the blade, and axially thereof to the atmospherethrough a plurality of angularly arranged apertures 40, Figure 2, located adja- I cent the trailing-edge of the blade. If desired, a supportng member 41 having a hub 42 threaded on the driving shaft and rotating therewith, may be. employed for-suitably supporting'the collector rings 31 ando c on. I

In order to prevent the heat of the exhaust gases from affecting the bearings provlded 1n the hub, a nember 43 having heat-resistant and heat-insulating qualities as for example a phenolic. condensation product, is suitably positioned witlnnand ad acent the inner end of each propeller blade as by passing the same intoIplace. Such member is effective. to confine the heated exhaust gases in that portion of the blade wherein high temperatures will not seriously afi'ect any "of the working parts.

Referring more particularly to Figure 2, there is disclosed therein a slightly modified 'form of'the' invention, whereina specially constructed propellerhub is employed, en-

abling the exhaust 'gasesto be conducted through the hub and thence through the blades to atmosphere' By such an arrangement, a more compact. structure is realized,

it being apparent from. an inspection of this figure that the collectin rings are of less diameter than those utilized in connection with the structure disclosed-in Figure '1'. As shown, each i hub socket 11 has integrally formed therewith aninwardly extending tubular extension which is adapted to be suitably secured as by welding, to the rotatable collector ring. 32. .The stationary collector ring 29 telescopes within the rotatable supported on the engine exmaining elel nts comprising thecombi'nm' ring and may tension 5 21s b means of ribs 44. The re- 4 tion disclosed in the alternative form, Figure 2, are similar to those described in detall in connection with Figure 1.

During operation of either form of the invention, it will be seen that as soon as the propeller is rotated, centrifugal force will be effective to withdraw the exhaust gases from the engine cylinders and discharge same to the atmosphere through the apertured blades. When it is desired to vary the pitch of the blades, axial movement of the rod 23" will cause a corresponding axial movement of each of the toothed racks 21, through movement of the member 22, such movement of the racks being effective to rotate the ring gears 20, securely attached to each blade and thus rotate the latter in their respective sockets.

There has thus been provided by the present invention a novel propeller construction wherein the exhaust gases of an engine may be conducted through the blades thereof to the atmsophere and wherein the pitch of the blades may be varied at will, during operation, and without interfering with the dis charge of the exhaust gases. By combining these two features into one compact structural arrangement, an unusually eflicient construction is attained and one in which maximum engine and propeller efficiency may be secured at all times. The provision of the heat-insulating member within the blade between the exhaust gases and the interior of the hub, permits the propeller assembly to be operated without fear of any danger of bearings being burned out because of the high heat content in the exhaust gases.

Though there has been illustrated and described only two embodiments of the invention, it is to be expressly understood that the same is not limited to the forms shown, but may be embodied in various mechanical alternatives. For example, means other than the gear and rack mechanism may be employed for changing the pitch of the blades while in operation. It is also to be under stood that various other changes ma be made in the sizes, shapes and relative locations of the component parts of the'propellei' without departing from the spirit of the invention, as will be understood by those skilled in the art. Reference will therefore be had to the appended claims for a defini} tion of the limits of the invention.

What is claimed is:

1. In an aeroplane propeller having a plu rality of hollow blades, means for rotating said propeller, means for conducting the exhaustgases from an engine to said hollow blades and means for varying the'pitch of said blades while the propeller is-rotating.

2. A propeller for aircraft comprising a rotatable shaft, a plurality of hollow blades drivably connected with said shaft, means for rotating the blades about their longitudinal axes to vary the pitch thereof while the propeller is rotating and means for leading being provided with openings,

the exhaust gases from an engine to the interior of said hollow blades.

3. In combination, a propeller having a plurality of hollow blades, means for rotating said propeller, means for continuously maintaining said hollow blades in communication with the exhaust manifold of an engine and means for varying the angularity of said blades while the propeller is rotating.

4. In combination with an internal combustion engine of the type having an exhaust gas manifold and adapted to rotate a propeller shaft, a plurality ofhollow blades drivably connected to said shaft said blades means for leading exhaust gases from said manifold to said hollow blades whereby during operation said gases willbe exhausted to the atmos' phere through said openings, and means for varying the pitch of said blades during rotation thereof.

5. A propeller comprising a hub, means including an engine for rotating the hub, a plurality of hollow blades carried by the hub, means for changing the pitch of said blades during rotation of the propeller, means for conducting the exhaust gases from the engine for conducting the exhaust gases from the engine to said hollow blades at points remote from the hub said means including a collector ring, and a manifold encirculing'each blade and connected to said ring.

7. A propeller comprising a hub, means including an engine for rotating the hub, a plurality of hollow blades carried by the hub, means for changing the pitchof said blades during rotation of the propeller, means for conducting the exhaust gases from the engine to said hollow blades said means including a collector ring, a manifold encircling ea'ch' blade and connected to said ring, and a. heat insulating member within each blade for heat insulating said hub from said gases.

8. In combination with a propeller having for rotating the hub, av

having a hollow hub communicating with the I exhaust of an engine, a plurality of hollow apertured propeller-blades carried by said hub and communicating therewith whereby during rotation of the propeller exhaust gases will be conducted through said hub and blades to the outside air, and means for changingthepitch of the blades at-willduring operation of the propeller.

.10. In a propeller having a pluralityof apertured hollow blades, a hub, means for rotating said hub, means including bearings for rotatably supporting said blades in said hub, means including-a manifold member encircling each blade for continuously maintaining the interior thereof in communication with an exhaust manlfold of an engine,

a member associated with the inner end of each bladefor heat insulating the exhaust gases from said bearings, and means'for rotating said blades about their longitudinal axes to vary-the .p'itch while said blades are being rotated by the hub. g 11. A propeller'having in combination, a.

rotatable shaft, engine means for rotating the shift,- a plurality ofapertured hollow blades,

a hub drlvably connected with the shaft, and

rotatably carrying said blades, means for continuously (maintaining, the interior of said blades in communication Withthe exhaust passages of the engine said means including blades in said hub to vary the pitch thereof during operation of the propeller.

. shaft and an engine for rotating said-bla .means for varying the pitch of the blades during such rotation, means for .conductin the exhaust gases from said engine to eac of said hollow blades and heat-resistant eIe- 1 ments positioned within each'of said blades forpreventing the heat. from the exhaust gases from being conducted .tosaid shaft.

13. A propeller comprising a rotatable shaft, a hub drivably connected to said shaft,

. a plurality of apertured hollow blads rotatably carried by said hub, means for rotating saidblades in said hub to vary the pitch thereof, and .a manifold encircling each-blade and communicating with a portion of the apertures therein for conducting fluid into 4 said blades.

14. A. propellergcomprising a rotatable shaft, a hub drivably connected to said shaft, a plurality of hollow blades rotatably carried ,by said hub, means for rotating said blades in said hub to vary the pitch thereof, each of said blades being provided with a plurality of apertures ad acenttheroot end 12. Anexhaust as propeller having a plu -ralityof hollow. lades, means including a es,

thereof, and amanifold encircling each blade adjacent said apertures.

1-5. A propeller comprising a rotatable shaft, engine means for rotating) said shaft,"

a plurality offhollow apertured lades drivably connected to said shaft, a manifold enand connections between said manifolds and the exhaust of said engine.

16. 'A propeller comprising a rotatable .shaft,-engine means for rotating said shaft, a plurality of hollow. apertured blades driv-.

ably connected to saidshaft, a manifoldencircling each of said blades andcommunicating with a portion of the apertures therein, a rotatable collector ring communicating 'withsaid manifolds and a stationary collec-- tor ring communicating with said rotatable collector 'ring and the exhaust of said engine.

In testimony whereof I have signed this specification.

GEORGE HOUSTON."

circling each of said blades and communicatp ing with a portion of the apertures therein, v

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